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General Epistemology        Chapter I-7       


Chapter I-7 Validity domain of a logic



What determines which logic is to be used for a given problem?


Some will say that these different logics result from cultures and mentalities different than Western rationality, in particular from the East, and that they would represent the operation of another mentality... I on the countrary say that the fact that such or such logic was historically found by such civilisation or such psychology is certainly very interesting to study, but that it does not have any relevance in a discussion on validity of logic. On the countrary, I claim that logic is universal, in the meaning that a logical reasoning, whatever it is, does not depend on the culture, the country or the person who does it. Everybody was perfectly aware, without openly admitting it, that Aristotelian logic does not apply to certain objects. To have found another logic which applies in this case is rather an extension of the universality of logics: with adding other logics, appropriate to the objects considered, we can reason on more objects, while arbitrary opinions are losing ground.


All the logics we studied all have basically the same statute: relations between objects or concepts, which make possible to make various types of reasoning. A logic or another applies according to the properties of the objects on which we reason, in the meaning of the first axiom of the Set Theory.

Aristotelian logic applies to objects 1) clearly separate from each other 2) meeting a criterion completely or not at all. We could even say that it is generated by these criteria, that it emanates from this type of objects, that it is one of their properties, that it describes their behaviour. (This is the reason for which we can confidently use this logic to guess their behaviour). These criteria are generally satisfied in the fields of mathematics, physics, techniques and economy, where Aristotelian logic could reign as a nearby absolute master and produce enormous results there. It starts to miss ambition in medicine and biology. At last in spirituality, politics, morals and society, confusions caused by reduction to the criteria above lead to incredible conflicts and suffering.

 Quadripolar logic relates to objects 1) separated or not 2) appearing according to two opposite aspects (Yin-Yang axis) more or less harmonised (dual/non-dual axis), more or less adequate with a goal, even simply more or less bad or good. This type of objects almost misses in physics (note 8) and techniques. Some problems in medicine and biology comply with this diagram. But most of the questions in policy, morals and society, and in the spiritual and esoteric fields (note 9) cannot be studied seriously without the diagram.


We however should not artificially create oppositions like Aristotelian logic being from the «material field» or «rational field» or «objective» whereas quadripolar logic would be from the «spiritual field» or «intuitive field» or «subjective». We can even less say that they exclude each other or that they have contradictory results: simply one is exact ant the other is false, case per case, for any considered object. We even not have the freedom to choose which one to use, as it is imposed by the object considered. Simply we rather meet the second in the fields of the mind, where Aristotelian logic still possesses large domains. Often, the diagram clarifies and gives a clear logical shape to a problem, with providing with a kind of map of it. Once this done, to manage displacements into this map is more strategy than Zen.


At last, we cannot demonstrate in an absolute way the veracity of a logic or an epistemology; we can only experience its operational effectiveness, in a field or on adapted objects, to solve problems and to use it. Lofti Zadeh's fuzzy logic gained its recognition in a very down to earth way, by driving subways with more flexibility than an human driver. If only this is requested for a logic to be recognised, then quadripolar logic has gained a much higher legitimacy while bringing new and effective conclusions in the examples of chapter I-4, allowing to avoid many social or psychological sufferings otherwise «impossible to fix».

Valid domain of a logic,
mistake of logic validity©
mistake of type of logic©

(Permalink) (note 93 on the use of © content) Generally, facing a new problem, we start with looking at the properties of the objects on which we shall work. If these objects have two exclusive values, true/false, yes/no, open/closed, it is the Aristotelian logic which is valid; if the object has a property which varies continuously or at random, it is a progressive or probabilistic logic; if the object presents two aspects which we can place in a Yin-Yang pair or a quadripolar diagram, then respectively these logics are valid. The set of objects which obey to a given logic is the domain of validity of this logic. To be mistaken at this level is a mistake of logic validity, or mistake of type of logic. But it can also be an effect of the psychological bias© as we shall see in the following chapter I-8.

Obviously the mistake of logic validity always leads to gross mistakes, even more than other reasoning mistakes. But these mistakes are more difficult to find.







General Epistemology        Chapter I-7       







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